Improvement in treating tanned leather



UNITED STATES PATENT OFFICE.

IMPROVEMENT IN TREATING TANNED LEATHER.

Specification forming part of Letters Patent No. 40,669, dated November 17, 1863.

To all whom it may concern:

Be it known that I, BENJAMIN H. LIGHT- FOOT, of Philadelphia, Pennsylvania, have invented an Improvement in the Treatment of Tanned Leather; and I do hereby declare the following tobe a full, clear, and exact description of the same.

My invention consists in the treatment of tanned leather by applying to the same, substantially in the manner described hereinafter, petroleum or any oily hydrocarbons holding paraffine in solution, in combination with t a llow or its equivalent, so as to rapidly reduce the leather to the desired pliable condition at a much less cost than by the application of the usual oily and greasy substances hitherto used for the same purpose.

In order to enable others skilled in the art of currying to practice my invention, 1 will now proceed to describe themanner of carryin g it into effect. l

I have found by practical tests, and after a series of very careful and long-continued experiments, that tanned leather can be reduced to the desired pliability by the application of petroleum or rock-oil or its equivalent at much less expense than by the use of the ordinary greasy and oily compounds, technically termed dubbing! Although I have used the crude petroleum as obtained direct from the oil-wells with marked success for the above purpose, some of the products of the distillation ofpetroleum may be employed with the best resultsas, for instance, the heavy oil used for lubricating machinery, the grease also used for lubricating purposes, and consisting of paraffine with a little oil. In fact, any hydrocarbons holding more or less paraffine in solution can be used, whether they be obtained by the distillation of coal, or found in a natural state, or obtained by the distillation of petroleum.

In carrying myinvention into effect I adopt I the following process: The tanned hideis first subjected to the preliminary soaking process adopted in currying leather, and is subsequently dressed and its inequalities removed by shaving and scouring-processes so well understood by those familiar with the art of curryin g that a lengthy description is unnecessary. The hide is then allowed to become partially or, as it is technically termed, half dried, after which it is ready for the application of the mixture of petroleum and tallow, or their equivalents.

The proper proportion of the'ingredients must be determined by the experience of the currier, as more tallow is required in warm weather than in cold weather.

The application is madein thefollowing manner: The hide in its half-dried state is placed on a table or slab and rubbed down by a suitable instrument until perfectly level. It is then coated over on the flesh side with the compound, care being taken that the entire surface is evenly covered. The hide or skin is then hung up and allowed to remain untouched for forty-eight hours, or thereabout, according to the thickness of the skin. 0n removal it will be found that the leather has been effectually penetrated by the petroleum, and that its fibrous tissues have become thorougly impregnated with the oily hydrocarbon and the paraffine held in solution by the latter, and that the leather has been reduced to the desired state of pliability, the tallow assisting to reduce it to that state. A ter 1e superfluous portion of the compound has been removed from the leather and the latter has been subjected to processes generally adopted after the application of the usual dubbing, the leather may be blackened, if desired, and is then ready for the market.

The composition may be applied to both sides of the hide; but its application to one side only will in most cases be sufficient.

Thetriflin g cost of petroleum compared with that of the usual tanners oil and the penetrating quality of the oily hydrocarbon render the above-described process one of ready accomplishment at a much reduced cost. At the same time the leather thus treated is of a quality equal, if not superior, to that treated by the usual dubbing.

I claim as my invention and desire to secure by Letters Patent The treatment of tanned leather by the application to the same, substantially in the manner described, of petroleum or any oily hydrocarbons holding paraffine in solution, in combination with tallow or its equivalent.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

BENJAMIN H. LIGHTFOOT.

Witnesses:

HENRY HowsoN, J OHN WHITE. 

